Floor area ratio. The floor area of the building(s) on a plot divided by the area of that plot. Base area (to determine the floor area ratio). For the purpose of determining the floor area ratio, the “floor area” of a building is the sum of the horizontal gross surfaces of the different floors of the building, measured by the exterior surfaces of the exterior walls or at the centre line of the walls separating two buildings. The “floor area” of a building includes the surface area of the basement if more than half of the height of the basement is above the specified sidewalk level or above the level of the prefabricated parcel if no sidewalk level has been determined; elevator shafts and stairwells on each floor, floor area for mechanical equipment, excluding appliances, open or closed; Located on the roof – penthouses, attic with clear height of seven feet, ten inches or more, interior balconies and mezzanines, and enclosed porches and floor space for accessory uses. However, areas reserved for off-street parking or charging may not be part of the “floor area”. The use of floor space appears to be limited in single-family and two-family areas. Without going into the explanations established for the site requirements, we can say that they impose a volume limit in addition to the maximum height restrictions. When these proportions are associated with maximum plot cover, we obtain a result that resembles an area ratio because it establishes a consistent relationship between the area and the volume of construction. They also ensure minimal separation between objects, which is not always achieved by controlling only the footprint ratio. When horizontal and vertical constraints are incorporated into a number, some flexibility in real estate design is possible. The advantage of treating base area as constant is that it is consistent with other zoning considerations.
Gross floor area: the sum of the horizontal gross surfaces of the different floors of all the buildings of the property, measured by the external surfaces of the exterior walls or at the axis of the walls separating two buildings. The ratio of soil to area is not a panacea. It gains value as a zoning device if the numerical value assigned to it contributes to the achievement of the objectives of the zoning ordinance while leaving more flexibility to structural planners. The first zoning bylaws were developed to limit the size of structures, but later the area ratio emerged as a new way for zoning codes to achieve their goal of regulating development intensity. The American Plan Association`s 1958 Study of Planning Advisory Services (PAS) reveals more about the origins of the FAR as a standard tool for plan execution. The floor area ratio would provide a great deal of leeway in the final form of a building if there were no other development limits. Other laws, such as height restrictions, restrict the allocation of area ratios in many parts of the United States and the rest of the world. Take, for example, an apartment complex for sale in Los Angeles, California. The apartment building is for sale for $3 million and spans 17,350 square feet. The total area of the property is 78,843 square feet, or 1.81 acres. 17,350 divided by 78,843 equals 0.22x or 17,350 divided by 78,843.
The surface ratio is a refinement of conventional mass controls. It expresses the mathematical relationship between the volume of construction and the unit of land in one measure instead of several. However, it does not control in any way the location of this volume on the ground. Therefore, if placement is a factor to be regulated, additional mass devices are needed. It is currently being hailed as a new and ingenious way to make zoning ordinances more flexible. Although some proponents argue that it can be autonomous as a mass control, most regulations that use it also retain some, if not all, common devices. In this report, we will look at the applications of the area ratio for commercial, industrial and residential areas, the details that make it attractive to urban planners, architects and builders, and some of its shortcomings. If we consider traditional bulk orders as a rigid shell, we can consider the floor area ratio as a hull with extendable dimensions.
Figure 1 shows the flexibility of the floor arrangement between controls that limit the gross floor area, but not the height – except indirectly. Here are some representative definitions of “floor area” and “floor area ratio”. In addition, the relationship between a public transport system and density in city centres is reciprocal. If the transportation system consists only of buses that run at four miles per hour on trade routes or, at their maximum efficiency, are only allowed to carry 1,200 people per hour, it would be unreasonable to encourage the construction of buildings with large gross floor areas. On the other hand, if the city centre is served by a metro with a capacity of 40,000 people per lane per hour, high-mass buildings are less likely to cause traffic jams. In other words, greater density – and therefore greater mass and taller buildings – is possible with greater transit capacity. As a result, a low floor area ratio is not always a good thing, and a high ratio is not always a bad thing. It depends on the area. Floor Area Ratio (FAR).
The “area ratio” of the building(s) located on land is the floor area of the building(s) on that land divided by the area of that land or, in the case of planned developments, by the net area of the land. In single-family and two-family areas, the use of the floor area ratio appears to be rather limited. Without going into the established justifications for the court`s requirements, we can see that they introduce volume control as well as maximum height restrictions. If a maximum parcel cover is added to these dimensions, we obtain a result that has the same effect as a floor area ratio, because in combination they create a constant ratio between the construction volume and the land area. (See diagram.) In addition, they ensure a minimum distance between buildings, which is not necessarily the result only of the regulation of the floor area ratio. Suppose the area ratio that a parcel of land should follow is 0.2. This means that the total or gross floor area of all buildings on the property should not exceed one-fifth of the total land area. As an example: a “light” industrial zone requires harmful industries and a large distance between facilities and ancillary uses on the one hand and surrounding residential areas on the other. It also has a low structural density, or a percentage of the total area covered by the structures.
These characteristics can be achieved through other bulk controls – mainly construction sites and the percentage of lot coverage. Since most facilities built today have no more than one floor, maximum height constraints do not limit the design of factories in the same way as the design of office buildings.